feat(content): function signatures + test cases

backend/data/questions/array-partition.yaml

@@ -9,6 +9,26 @@ categories:
 patterns:
   - greedy
 
+function_signature: "def array_pair_sum(nums: list[int]) -> int:"
+
+test_cases:
+  visible:
+    - input: { nums: [1, 4, 3, 2] }
+      expected: 4
+    - input: { nums: [6, 2, 6, 5, 1, 2] }
+      expected: 9
+  hidden:
+    - input: { nums: [1, 2] }
+      expected: 1
+    - input: { nums: [1, 1, 1, 1] }
+      expected: 2
+    - input: { nums: [-1, -2, -3, -4] }
+      expected: -6
+    - input: { nums: [-5, 5, -3, 3] }
+      expected: -2
+    - input: { nums: [1, 2, 3, 4, 5, 6] }
+      expected: 9
+
 description: |
   Given an integer array `nums` of `2n` integers, group these integers into `n` pairs `(a1, b1), (a2, b2), ..., (an, bn)` such that the sum of `min(ai, bi)` for all `i` is **maximised**.